The Ethereum hashing function, keccak256, sometimes (erroneously) called sha3

Note: the similarly named pyethash has a completely different use: it generates proofs of work.

This is a low-level library, intended to be used internally by other Ethereum tools. If you're looking for a convenient hashing tool, check out eth_utils.keccak() which will be a little friendlier, and provide access to other helpful utilities.

Read more in the documentation on ReadTheDocs. View the change log.

python -m pip install "eth-hash[pycryptodome]"

>>> from eth_hash.auto import keccak
>>> keccak(b'')
b"\xc5\xd2F\x01\x86\xf7#<\x92~}\xb2\xdc\xc7\x03\xc0\xe5\x00\xb6S\xca\x82';{\xfa\xd8\x04]\x85\xa4p"

See the docs for more about choosing and installing backends.

If you would like to hack on eth-hash, please check out the Snake Charmers Tactical Manual for information on how we do:

• Testing
• Pull Requests
• Documentation

We use pre-commit to maintain consistent code style. Once installed, it will run automatically with every commit. You can also run it manually with make lint. If you need to make a commit that skips the pre-commit checks, you can do so with git commit --no-verify.

You can set up your dev environment with:

git clone git@github.com:ethereum/eth-hash.git
cd eth-hash
python -m virtualenv venv
. venv/bin/activate
python -m pip install -e ".[dev]"
pre-commit install

To release a new version:

make release bump=$$VERSION_PART_TO_BUMP$$

The version format for this repo is {major}.{minor}.{patch} for stable, and {major}.{minor}.{patch}-{stage}.{devnum} for unstable (stage can be alpha or beta).

To issue the next version in line, specify which part to bump, like make release bump=minor or make release bump=devnum. This is typically done from the master branch, except when releasing a beta (in which case the beta is released from master, and the previous stable branch is released from said branch).

If you are in a beta version, make release bump=stage will switch to a stable.

To issue an unstable version when the current version is stable, specify the new version explicitly, like make release bump="--new-version 4.0.0-alpha.1 devnum"